As has already been stated, our state comprises several major and minor lake systems. Lake Kolleru is identified as the largest fresh water lake system in Asia. The major salt-water lake in A.P. is lake Pulicat located in the Nellore district.
| Water class | Electrical | Alkali (Rs. in Lakhs) |
| (micro-mhos at 25oC) | Conductivity | hazard |
| (SAR) | Excellent <250 | upto 10 |
| Good | 250-750 | 10-18 |
| Medium | 750-2250 | 18-25 |
| Bad | 2250-4000 | 26 |
| Very Bad | >4000 |